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Title: Characterization of microstructure and texture across dissimilar super duplex/austenitic stainless steel weldment joint by super duplex filler metal

In the present paper, microstructural changes across an as-welded dissimilar austenitic/duplex stainless steel couple welded by a super duplex stainless steel filler metal using gas tungsten arc welding process is characterized with optical microscopy and electron back-scattered diffraction techniques. Accordingly, variations of microstructure, texture, and grain boundary character distribution of base metals, heat affected zones, and weld metal were investigated. The results showed that the weld metal, which was composed of Widmanstätten austenite side-plates and allotriomorphic grain boundary austenite morphologies, had the weakest texture and was dominated by low angle boundaries. The welding process increased the ferrite content but decreased the texture intensity at the heat affected zone of the super duplex stainless steel base metal. In addition, through partial ferritization, it changed the morphology of elongated grains of the rolled microstructure to twinned partially transformed austenite plateaus scattered between ferrite textured colonies. However, the texture of the austenitic stainless steel heat affected zone was strengthened via encouraging recrystallization and formation of annealing twins. At both interfaces, an increase in the special character coincident site lattice boundaries of the primary phase as well as a strong texture with <100> orientation, mainly of Goss component, was observed. - Graphical abstract: Displaymore » Omitted - Highlights: • Weld metal showed local orientation at microscale but random texture at macroscale. • Intensification of <100> orientated grains was observed adjacent to the fusion lines. • The austenite texture was weaker than that of the ferrite in all duplex regions. • Welding caused twinned partially transformed austenites to form at SDSS HAZ. • At both interfaces, the ratio of special CSL boundaries of the primary phase increased.« less
Authors:
 [1] ;  [1] ;  [2] ;  [3] ;  [4]
  1. Department of Materials Engineering, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)
  2. Department of Materials Engineering, Shiraz University, Shiraz 71348-51154 (Iran, Islamic Republic of)
  3. Department of Natural Resources, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)
  4. Department of Mechanical Engineering, University of Saskatchewan, Saskatoon SK S7N 5A9 (Canada)
Publication Date:
OSTI Identifier:
22476121
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 106; Other Information: Copyright (c) 2015 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; ANNEALING; AUSTENITE; AUSTENITIC STEELS; BACKSCATTERING; ELECTRON DIFFRACTION; FILLER METALS; GAS TUNGSTEN-ARC WELDING; GRAIN BOUNDARIES; HEAT AFFECTED ZONE; INTERFACES; METALS; OPTICAL MICROSCOPY; RECRYSTALLIZATION; STAINLESS STEELS; WELDED JOINTS